1. Field of the Invention
The present invention relates to a method for mixing liquids, and a liquid mixing apparatus. More particularly, it relates to a method and an apparatus for allowing liquids to mix each other by their diffusion after forming a laminated structure of the liquids in the states of thin layers.
2. Description of the Relate Art
As one apparatus for mixing plural kinds of fluid effectively, for example, Japanese Patent Application Publication No. 2005-77219 proposes a microdevice which joins the plural kinds of fluid to flow together into an inlet of a microflow passage being a flow passage of a micron order, and enables to homogeneously mix them each other in an instant. As shown in FIG. 4, the microdevice is formed as a Y-shaped flow passage composed of a micro flow passage 114 which allows a plurality of fluids F1 and F2 to flow as a wafer-shaped laminar flow and causes them to mix each other or to react each other accompanied by mixing, and of two fluid supply passages 118A and 118B for feeding the fluids F1 and F2. Then, the fluids F1 and F2 fed into the fluid supply passages 118A and 118B are made to join each other at a joining portion 120 each other as to flow through one micro flow passage 114. While the fluids F1 and F2 are caused to flow as a wafer-shaped laminar flow, they are allowed to mix and react each other, the resultant mixed and reacted liquid FM is discarded from a trailing end of the micro flow passage 114.
When the flow passage is micronized as described in Japanese Patent Application Publication No. 2005-77219, a mixing effect by molecular diffusion becomes great. A diffusion time by the molecular diffusion is affected by square of a distance as shown in the equation: T=L2/D (D: a diffusion coefficient; L: a typical distance over which molecules diffuse and reach during a time T). Accordingly, it becomes important that how thin the thickness of the laminated body made by laminating plural kinds of liquid which diffusively mix each other is reduced. Therefore, it is necessary that the flow passage of the microdevice is formed into the flow passage having a minute width.